The subject matter disclosed herein relates to an exhaust aftertreatment system for an internal combustion engine and, more specifically, to controlling a reductant injection.
Engines (e.g., internal combustion engines such as reciprocating engines or gas turbines) combust a mixture of fuel and air to generate combustions gases that apply a driving force to a component of the engine (e.g., to move a piston or drive a turbine). Subsequently, the combustion gases exit the engine as an exhaust, which may be subject to exhaust treatment (e.g., aftertreatment) systems that include one or more catalytic converters (e.g., selective catalytic reduction (SCR) assembly) to reduce the emissions of nitrogen oxides (NOx) by converting NOx and other emissions to less harmful byproducts. However, the reductant levels have to be controlled precisely to achieve the desired NOx reduction.